The invention relates to a spiral pertaining to a turbomachine, the spiral having a number of interconnected segments and at least one parallel plate, and also relates to a use of such a spiral in a water power station.
The spirals of turbomachines, such as turbines, pumping turbines or pumps, are formed, as a rule, from individual segments welded to one another. In this case, the spiral becomes the more beneficial in terms of stress and flow, the more segments are provided. On the other hand, the more segments are provided, the more costly a spiral becomes. For this reason, spirals are manufactured, instead, with fewer segments, the stress peaks which occur at the transitions of the spiral to the parallel plate being absorbed by corresponding sheet metal thicknesses of the spiral skin. Flow-related disadvantages are in this case taken into account.